Some tips for the newcomers:
The control scheme is:
X ([]) = Light Punch (press twice and the second punch will be a Medium punch)
Y (/\) - Heavy Punch
A (X) - Light Kick (press twice and the second kick will be a Medium kick)
B (O) - Heavy Kick
RB (R1) - Assist One = Pressing this button will call your first partner to come and do a special attack. You will notice that when you press Assist One the character whose life bar is DIRECTLY below your current playable character.
RT (R2) Assist Two = This will call your second partner and it's the character whose lifebar is the last of the 3rd (the one at the most bottom).
Meaning if you picked Sentinel/Cable/Storm in that order, pressing RB while Sentinel is out will cause Cable to perform an Assist. Pressing RT will cause Storm to perform an Assist.
My recommended control configuration for this game is:
Triggers = Assists
Shoulder Buttons = Two punches and Two Kicks so that doing supers is easier
You can also make the Shoulder buttons Both Lights/Both Strong which will allow you to switch characters (more on this latter).
Some extra stuff:
Switching Characters: Both of the Light Attacks at the same time (Light Punch + Light Kick) will switch to your second character (the character that will be switched is the one who is on Assist 1). Both of the Heavy attacks at the same time (High Punch + High Kick) will switch to your third character.
Meaning if you have Sentinel/Cable/Storm, press X+A will switch to Cable (and this will make Sentinel the character on Assist 1). If you press Y+B it will switch to Storm (and Cable will be at Assist 2).
Note that when you switch characters, they will come in doing an attack that will launch your opponent if it connects. If the opponent blocks the attack, your new character is left opponent to a world of hurt because when they switch in they ALWAYS taunt. So be careful when you switch...
Super Jump: Press crouch (down) and then quickly press jump (up). Your character will jump really high in the air.
Dash Forward/Backwards: Forward, forward or back, back quickly. You can also press forward + PP (light punch plus heavy punch) to dash forward.
Performing Launchers: Every character has either one or more ways that they can LAUNCH the opponent in the air with. This is normally done with one of the following commands: Crouching + High Punch [down+Y(/\)], Standing Medium punch (press Light punch twice) or standing High Kick (B/O).
After you launch an opponent, you can do a FOLLOW UP aerial combo by pressing UP. This will automatically do a super jump and you will come at the same level as your launched opponent. This will be an aerial combo from now on (more on this later).
If your team is Sentinel/Cable/Storm, their launchers are: Sentinel: Standing High Kick, Cable: Standing Medium Punch, Storm: Crouching High Punch or Standing High Kick
Performing Air Combos: After doing a launcher and pressing UP to follow up, you can do a bread and butter aerial combo using the following combo set: Light punch, light kick, light punch, light kick, high punch and/or high kick. This is the most basic type of air combo out there, normally after you do the first 3 or 4 hits you can do a Special attack like an Air Hadouken as a finisher. The aerial combos in this games are quite insane as most of you will soon find out.
Performing Special moves: Every character has a bunch of special moves that cancel your normal attacks. These are the QCF/B (quarter circle forward) moves or the HCF/B (half circle forward or back) or the dragon punch motion (forward, down, down/forward) that are the STAPLES of the Street Fighter series. A lot of the moves can be performed in the air.
Ex:
Cable: QCF+P = Hyper Beam
Dragon punch + P = Scimitar
QCB + K = Grenade
Performing Super Moves: Just about every super move in the game can be done by either a QCF/B or a HCF/B motion plus two punches or two kicks. Performing these moves will take away one bar from your super gauge (you can hold up to 5).
Ex:
Cable: QCF + PP = Hyper Viper Beam
QCF + KK = Time Flip
Performing Simultaneous Supers: This is where you do supers TOGETHER with one or more of your partners. This requires at least 2 super bars. If you have 2 bars, you will do a dual super where your current character and your Assist 1 character do supers (note that what super you and your partner do depends upon what Assist Type they have).
If you have 3 bars, all 3 of your characters will perform supers (again, which super they do depends on your assist type for all the characters).
This is done by pressing both the two assist buttons together.
Performing Consecutive/Delayed Supers: This is where you perform a normal Super which is followed by a super of your NEXT character. This requires at least 2 bars as well. For example, when you do Cable's super (Hyper Viper Beam)... while you do Cable's super you can perform the input for the super for your NEXT character (which is Sentinel and his super is QCF+KK). Cable's Hyper Beam will be cancelled with Sentinel's super. While doing Sentinel's super (if you have another super gauge) you can perform the super for Storm's super (QCB+PP) which will cancel Sentinels super with Storm's.